Uploading a custom header image to the twentyeleven theme in Wordpress

This is more of a note to myself.

Right now, I am tasked with customizing the twentyeleven theme into another theme , and it involves turning off the rotating header images. After unsuccessfully doing a walkthrough of the associated code (that begins in header.php with a call to header_image()), I found the functions.php file under wp-content/themes/. In the twentyeleven_setup() function, I found a call to register_default_headers, which takes in an associative array. I only need one header image, so I deleted all but one key-value pair, renamed the key to something that made sense, and pointed the 'url' key to the photo filename. Now, although I haven't deleted any of the other header images from the directory structure, the code will only pick up the one header image I registered.